Mercury arc rectifier



July 26, 1932. c, KRAMER 1,869,156

MERCURY ARC RECTIFIER Filed Oct. 4, 1929 Inventor:

Ch1-i than K 'a':.mer-

His Atiiorneg.

Patented July 26, 1932 CHRISTIAN KRAMER, or BEBLIN -ZPANKOW, GERMANY, AssIeNoR' roi'annnnangnrnc- TRIO. COMPANY, A.C.ORPOBATION OF NEW YORK Mnncnmr AnonEcTIrI n Application filedflctober. 4, 1929, Serial No.

My invention relatesto rectifier s, and has: for its principal objectthe provision of'anL improved anode'structure whereby the current carrying capacity of the" rect1fier.- is greatly increased.

The power carryingcapacity of'rectifiersi such as the mercury arc is limited by arc backs occurring when the individual anode.

current exceeds a certainvalue, This cur:- rent differs for each operating voltage. and

I vapor pressure but there is: a definite-valve for each set of conditions above which: itis impossible to load a rectifier. In. order'to increase the total power carrying capacity of a rectifier, it is customary to increase; the number of anodes. Thisincreasein .the number of anodes is objectionable becauseof the accompanying increase in the. number. of seals, increase in the size: of. the tank, and complications in the connections.

In accordance with my invention these: ob,- jections are overcome in that, instead of the plurality of parallel anodes, I provide an anode structure comprising a single anode stem arranged to be sealed into the tank and to support a plurality of anodes, a shield being arranged to surround the structure and provide an individual arc path to each of said anodes.

My invention will be better understood from the following description when consid-v ered in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 illustrates a section of a rectifier provided with anode structures built in accordance with my invention; Figs. 2 and 3 illustrate other sec- 7 tional views of the anode structure illustrated in Fig. 1; Fig. 4 is a diagrammatic view of the rectifier illustrating the paths of arcs traveling between the cathode and the anode circuit; and Figs. 5, 6, 7 and 8 illustrate modifications of the invention.

Fig. 1 illustrates a partial cross-section of a rectifier 10 provided with anode structures 11 surrounded by shields 12. The structure 11 is supported by, and insulated from the tank 10, by an insulater 13 and comprises a stem 14 provided with a long flattened por- 397,398, and in Germany January 3'0, 1929.

tion 14'. upon whichthe arc receiving members. or anodes 15 aremount'ed. -The anodes. l5. are..'arranged.in vertical order upon" the. stem: 14? They may be made of iron, graph. iteor. any OthGIISllltELb'lB. material which is not attacked by mercury'vapon. The shield 12v surrounds. the structure. and may bewpro- I vided on. its outer side with a slot. Preferably, however, the shield 12 is provided. with a pluralityof openings provided withinserts; 16. which formashortv lengths of tubingat-- tached to the'shield and are arranged to.eX-;

tend: into close; proximity .to the ends. of" anodes- 15, and registerwith theeactive surfaces of the. anodes, thereby.- forming effective are. paths to eachanoder Fig. 2 is. across-section view throughthe shield. 12,.insulator13' and anode 15, illustratingythe front elevation of stem 14!. Fig. 3 is: a horizontal. cross-section view through shield 12 illustrating the arrangementof an insert 16in relation tor an anode15. Fig. is a' diagrammaticvicw. of; a rectifier. 10. illustratingby lines 17 the paths of. arcsi traveling: between: the. cathode 18 and, the anodesl5.: 1f

, Figs. 5, 6, ,7 and 8 illustrate modifications: of the anode structurefland'methods for ob-.-

individual taining equal division of current betweenthe anode. Fig. 5 is a; horizontal cross-section view of shield 12 provided with inserts. 19

arranged to extendaround anode '15.. A col 1 lar5-20ofmagritic material, such asironifor.

example, istmounted upon :insert. 19, in i order to actas an archchoke,. SincePthechOking effect; is proportional ,to the; current flow, asubstantially equal division, of. the current between the. 1 different ano.des.-15 -isobtained.

Fig. 6 illustrates a modification ofthein ventions-imilar to Fig. 5.in which. an insert 21, made of insulating. material is used ande an insulating shield. 22, isiprovided. between.

the: steml l and the insert.21.. Inthis modi fication the insert 21. is lengthened to extend up'to the-insulatingshield 22 and isallowed to project beyondthe shield-12. The. collar 20. inthis modification. effects the equal division offthe current in the same manner asthe. construction.illustrated-in Fig. 5.; lengths ening of the insert and the provision of; the

insulating shield 22 which may be of mica, ceramic or any other material, affords protection of the stem 14: against the heat of the arc.

Figs. 7 and 8 illustrate a modification of the stem 14., Figs. 7 and 8 are respectively a front elevation and a side elevation of this modification. In Fig. 8 the stem and attached anodes 15 are shown in operating position in a. rectifier 10,the anode structure being surrounded by the shield 12 provided with the lengths of tubing 16 having openings registering with the active surfaces 6f the separate anodes. In order to obtain an equal divisionof current between the anodes 15, the stem li isdivided into laminations 23 having insulation between them. Each member 15'is attached to .one of the laminations 22 and in suchv manner that the anode farthest away from the cathode is attached to a lamination having the least resistance whereas the member 15 closest to the cathode is attached to the lamination having the highest resistance so that the total voltage drop between the-anode terminal and the cathode will be substantially the same for" all anodes 15 What I claim as newand desire to'secure by Letters Patent" of the United States is: lJAn anode structure for a rectifier including a stem, a plurality of anodes mounted one below the other upon said stem and projecting laterally therefrom, and a shield surrounding said stem and anodes and provided with openings registering with each of said anodes; v. 1

2. An anode structure for a vapor dischargedevice, including a stem, said stem having a resistance-which increases toward the lower part thereof, "a plurality of anodes mounted one below the other upon said stem and projecting-laterally therefrom, and a shield surrounding said stem and anodes and provided with a plurality-of openings registering with said anodes respectively.

3. An anode structure for a vapor discharge device-including a stem, a plurality of anodes mounted'upon said. stem, and-a shield surrounding said stem and anodes and providedwitha plurality of openings which register with said anodes respectively, and tubes mounted in said openings and extending from said shield toward said,

anodes. a v

: L-An anode structure for a vapor discharge device including a stem, offanodes mounted upon said stem, and'a shield surroundingsaid stem andanodes and provided with a plurality of openings reg istering with said anodes'respectively, tubes mounted in said op'eni'ngs and arranged to surround said anodes, and a plurality of shields of insulatinglmaterial disposed respectively. between said stem and the ends of said tubes.

a plurality and surrounding said anodes.

6. An anode struct'ure for a vapor discharge device includinga stem, a plurality of anodes-mounted uponsaid. stem, a shield surroundingsaid stem and anodesand provided with a plurality of openings registeranodes respectively, insulating ing with said tubes" mounted in said openings and surrounding said anodes, and rings of magnetic material surrounding said, tubes.

7. An anode structure for a vapor discharge device providedwith. a stem including laminations having a predetermined resistan ce to current flow, an anode attached to each of said laminations and a shield surrounding said stem and anodes and provided with openings registering with said anodes respectively. Y a I v l 8. An anode structure for anelectric dis charge device including a cathode, said structure being provided thelaminations of said stem being insulated from one another and having a predetermined resistance to current flow, and anodes mounted upon said laminations, the anode nearest tothe cathode being mounted upon the lamination having the greatest resistance.

In witness whereof, I have hereunto set my hand this 18 day of S eptember, 1929.

;' CHRISTIAN KRAMER.

with a laminated stem,- 

